We bought our robotic arm kit from Amazon. It has the pieces and parts to the kit. The kit was $119.99.

Down below is the link to the kit:  https://www.amazon.com/LewanSoul-LeArm-Con/dp/B074T6DPKX/ref=sr_1_1_sspa?ie=UTF8&qid

Our team has been assembling the robotic arm using this video tutorial: